Dear Hariom,

Inconsistent results were reported for diclofenac. Median concentrations of diclofenac in German streams (Elbe, Rhine and Main) rarely exceeded values of 50 ng L−1, and were restricted to small rivers that acted as receiving waters for communal wastewater plants.

There is NO permission limit yet.

For more details, please see our attached paper and references therein.

Hoping this will be helpful,

Rafik

In case of Diclofenac, permissible limit is still in demand. In a study, Diclofenac concentrations of 1000-2000 mg/l in zebrafish (Danio rerio) cause delay in hatching.

According to Ashton, Hilton & Thomas (2004), 424 ng/l level had been observed in the aquatic environment in the United Kingdom.

There is a demand on surfacewater in the EU as derivative of the water framework directive to keep below 100 ng/L. depending on the dilution of wastewater into the surface water this will have implications on wastewater.

E.g. if a surface water contains 50% treated wastewater and th 100 ng/L apply, then the wastewater effluent must keep below 200 ng/L. If you have only 10% wastewater in the surface water you are OK as long as the wastewater keeps below 1000ng/L